197 research outputs found

    The Radish Gene Reveals a Memory Component with Variable Temporal Properties

    Get PDF
    Memory phases, dependent on different neural and molecular mechanisms, strongly influence memory performance. Our understanding, however, of how memory phases interact is far from complete. In Drosophila, aversive olfactory learning is thought to progress from short-term through long-term memory phases. Another memory phase termed anesthesia resistant memory, dependent on the radish gene, influences memory hours after aversive olfactory learning. How does the radish-dependent phase influence memory performance in different tasks? It is found that the radish memory component does not scale with the stability of several memory traces, indicating a specific recruitment of this component to influence different memories, even within minutes of learning

    Search for Pauli Exclusion Principle Violating Atomic Transitions and Electron Decay with a P-type Point Contact Germanium Detector

    Full text link
    A search for Pauli-exclusion-principle-violating K-alpha electron transitions was performed using 89.5 kg-d of data collected with a p-type point contact high-purity germanium detector operated at the Kimballton Underground Research Facility. A lower limit on the transition lifetime of 5.8x10^30 seconds at 90% C.L. was set by looking for a peak at 10.6 keV resulting from the x-ray and Auger electrons present following the transition. A similar analysis was done to look for the decay of atomic K-shell electrons into neutrinos, resulting in a lower limit of 6.8x10^30 seconds at 90 C.L. It is estimated that the MAJORANA DEMONSTRATOR, a 44 kg array of p-type point contact detectors that will search for the neutrinoless double-beta decay of 76-Ge, could improve upon these exclusion limits by an order of magnitude after three years of operation

    Low Background Signal Readout Electronics for the MAJORANA DEMONSTRATOR

    Full text link
    The MAJORANA DEMONSTRATOR is a planned 40 kg array of Germanium detectors intended to demonstrate the feasibility of constructing a tonne-scale experiment that will seek neutrinoless double beta decay (0Ξ½Ξ²Ξ²0\nu\beta\beta) in 76Ge^{76}\mathrm{Ge}. Such an experiment would require backgrounds of less than 1 count/tonne-year in the 4 keV region of interest around the 2039 keV Q-value of the Ξ²Ξ²\beta\beta decay. Designing low-noise electronics, which must be placed in close proximity to the detectors, presents a challenge to reaching this background target. This paper will discuss the MAJORANA collaboration's solutions to some of these challenges
    • …
    corecore